Resize & Compress Images Online

Downscaling (reducing dimensions) does not inherently degrade quality if the aspect ratio is preserved and a good resampling method is used; most perceived loss comes from aggressive lossy compression rather than the resize itself. Pour un rendu net, gardez l'aspect ratio, utilisez une interpolation de qualité, puis ajustez la compression jusqu'à un point visuellement "lossless".

For photos, use WebP or AVIF (smaller than JPEG at similar visual quality); for graphics/transparency, use PNG or WebP lossless; for pure vectors, use SVG. If compatibility is critical, offer a WebP/AVIF primary with JPEG/PNG fallback via content negotiation or build step.

Lock the aspect ratio so width and height scale together and avoid stretching; many tools call this "Maintain aspect ratio" or "Constrain proportions." If a fixed box is needed, use fit/contain (letterboxing) or cover/crop to match the target without distortion.

Start around 70–80% for JPEG, or a mid-quality preset for WebP/AVIF, then visually inspect edges, gradients, and skin tones. If you see banding or halos, raise quality slightly; if not, try reducing a bit more to minimize bytes.

Yes—SocialPixOptimizer applies proportional resize and calibrated compression to target a visually lossless result while minimizing file size. You can balance speed and quality by picking the output format (WebP/JPEG/PNG) and quality preset that fits the use case.

Yes—SocialPixOptimizer can resize proportionally and compress efficiently for fast-loading social posts, headers, and ads. Combine it with your platform-specific pages (fixed dimensions) or use the Simple Resize page for quick global optimization.